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Benzene

Synonyms & Trade Names
Benzol, Phenyl hydride
CAS No.
71-43-2
RTECS No.
DOT ID & Guide
1114 130
Formula
C₆H₆
Conversion
1 ppm = 3.19 mg/m³
IDLH
Ca [500 ppm]
See: 71432
Exposure Limits
NIOSH REL
Ca TWA 0.1 ppm ST 1 ppm See Appendix A
OSHA PEL
[1910.1028] TWA 1 ppm ST 5 ppm See Appendix F
Measurement Methods
NIOSH 1500 , 1501 , 3700 , 3800;
OSHA 1005 , 5000
See: NMAM or OSHA Methods
Physical Description
Colorless to light-yellow liquid with an aromatic odor. [Note: A solid below 42°F.]
Molecular Weight
78.1
Boiling Point
176°F
Freezing Point
42°F
Solubility
0.07%
Vapor Pressure
75 mmHg
Ionization Potential
9.24 eV
Specific Gravity
0.88
Flash Point
12°F
Upper Explosive Limit
7.8%
Lower Explosive Limit
1.2%
Class IB Flammable Liquid: Fl.P. below 73°F and BP at or above 100°F.
Incompatibilities & Reactivities
Strong oxidizers, many fluorides & perchlorates, nitric acid
Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, nose, respiratory system; dizziness; headache, nausea, staggered gait; anorexia, lassitude (weakness, exhaustion); dermatitis; bone marrow depression; [potential occupational carcinogen]
Target Organs
Eyes, skin, respiratory system, blood, central nervous system, bone marrow
Cancer Site
[leukemia]
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet (flammable)
Change:No recommendation
Provide:Eyewash, Quick drench
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

(See Appendix E)

NIOSH

At concentrations above the NIOSH REL, or where there is no REL, at any detectable concentration:


(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0015   MEDICAL TESTS: 0022
Page last reviewed: October 30, 2019